Oil burning combustion head



1966 w. E. GUSTAFSON ETAL 3,285,315

OIL BURNING COMBUSTION HEAD Filed Jan. 27, 1964 United States Patent acorporation of Iowa Filed Jan. 27, 1964, Ser. No. 340,419 4 Claims. (Cl.158-76) This invention relates to an improved oil burner combustion headwhich is adapted to provide a generally improved performance for the oilburner.

In constructing an oil burner, a number of important factors are to betaken into consideration, and although there are various types of oilburners on the market, most such devices have one or more drawbacks. Forexample, one problem encountered with most types of oil burners is flamepulsation, which results in an inefficient use of fuel. Efliciency ofcombustion may also be improved by providing an intimate mixing of airand atomized oil. The oil burner flame should also be stable and quiet,and the oil burner construction should also provide smooth and efiicientignition or starting of the burner for each cycle. Although some priorart devices may overcome many of such design problems associated withoil burner construction, none are known to overcome such problems to thedesired extent by simple and economical construction.

It is therefore an important object of this invention to provide animproved oil burner by providing a combustion head therefor whereindisadvantages of prior art devices are substantially avoided.

It is also an object of this invention to provide an im proved oilburner combustion head wherein an improved mixing of air and atomizedoil is provided.

It is a t'urther object of this invention to provide an improved oilburner combustion head wherein a stable, quiet flame results.

It is another object of this invention to provide an improved combustionhead for a domestic oil burner wherein smooth ignition or starting ofthe flame is provided for each cycle.

It is still a further object of this invention to provide an improvedcombustion head for a domestic oil burner wherein pulsation of the flameis substantially avoided.

It is still another object of this invention to provide an improvedcombustion head for an oil burner wherein the combustion head includes acentral disc having an opening which is aligned with the air spraynozzle and vanes or openings are provided in the annular portion of thedisc in order to create air currents which are adapted to maintain theburner flame in close proximity to the disc.

It is yet a further object of this invention to provide an improved oilburner combustion head wherein the combustion head has a coned end whichpreheats some of the combustion air, whereby the preheated air assistsin providing a high-1y efficient and clean burning flame.

Further purposes and objects of this invention will appear as thespecification proceeds.

A particular embodiment of the present invention is illustrated in theaccompanying drawings, wherein:

FIGURE 1 is a longitudinal sectional view through my improved oil burnercombustion head, shown in conjunction with an air supply tube and an oilspray nozzle;

FIGURE 2 is a sectional View taken along the line 22 of FIGURE 1;

FIGURE 3 is a sectional view taken along the line 3-3 of FIGURE 2; and

3,285,316 Patented Nov. 15, 1966 FIGURE 4 is a sectional view takenalong the line 4-4 of FIGURE 2.

Referring to the drawings, my improved combustion head 10 is shown insecure attachment to the outer end 12 of an air supply tube 14. As shownin FIGURE 2, both the air supply tube 14 and the combustion head 10 aresubstantially circular in cross-section, the combustion head 10 beingadapted to telescope Within the air tube 14 so that the outercylindrical surface of the combustion head housing 16 and the innercylindrical surface of the air tube 14 are in intimate or sealingcontact. The head 10 is fastened to the air tube 14 by any suitablemeans, as by a sheet metal screw 18. Centrally, positioned within theair tube 14 is an oil spray nozzle 20, which is adapted to provide afine spray of oil, suitable for eflicient combustion. Ignition of theatomized oil emitting from the nozzle 20 is provided by an electricspark passing between a pair of electrical ignition points or leads 22adjacent the nozzle 20.

The housing 16 of the combustion head 10 includes a cylindrical portion24, which is maintained in intimate or sealing contact with the air tube14, and is also provided with an inwardly coned end portion 26, whichprojects outwardly from the end 12 of the air supply tube 14. The cone26 terminates as a rim 28 which surrounds a central aperture 30, throughwhich the burner flame F passes.

A generally circular metallic plate or disc 32 is mounted along theinner periphery of the cylindrical wall of the combustion head housing16. The disc 32 is mounted transverse, preferably perpendicular, to theaxis of the combustion head 10 and the air tube 14 and is locatedintermediate the air nozzle 20 and the coned end 26 of the housing 16.The disc '32 has its outer edge or periphery '34 in substantiallycontinuous contact with the inner periphery of the combustion headhousing 16, thereby allowing little if any passage of air between thehousing 16 and the outer edge 34 of the disc 32.

The circular plate 32 also includes a central opening 36 which is insubstantial alignment with the oil spray nozzle 20 and with the centralaperture 30 formed by the rim 28 of the cone 26. The central opening 36is of a smaller diameter than the aperture 30 at the coned end 26. Anannular portion 38 of the disc 32 is defined between the outer periphery34 of the disc 32 and the central opening 36. The anular portion 38includes a first or inner set of vanes or louvers 40, which defineopenings 41, and a second or outer set of vanes 44, which defineopenings 45. The first set of vanes 40 are spaced inwardly a shortdistance from the central opening 36, a rim 42 being locatedtherehetween. The air-directing vanes 40 are spaced at substantiallyequal distances from each other and are also spaced inwardly from thecentral opening 36 at substantially equal distances. The outer set ofopenings of air-directing vanes 44 are also spaced a substantialy equaldistances from each other and from the central opening 36 of the disc32. An outer rim 46 is provided on the disc 32 between the vanes 44 andthe outer periphery 34 of the disc 32. Dimensionally, the second orouter set of vanes 44 are larger than the inner set of vanes 40, but thenumber of vanes in each set are equal to each other, as they arestaggered with respect to each other, as shown in FIGURE 2.

Each set of vanes 40 and 44 may be simultaneously formed in the annularportion 38 of the disc 32 by any suitable means, as by stamping. The airpassages or openings 41 and 45 defined by the vanes 40 and 44 are in aplane transverse to the plane of the disc 32 or, in

other words, are in substantial alignment with the axis of thecombustion head 10. Referring to FIGURES 3 and 4, cross-sectional viewsof the outer set of vanes 44 and the inner set of vanes 40 are shown.Both sets of openings 41 and 45 are defined by the forward edge of onevane and the trailing edge of the adjacent vane. The air openings 41 and45 cooperate with the vanes 40 and 44 t direct air in a directionsubstantially transverse to the axis of the combustion head to thusinitially provide a swirling movement of air in the chamber defined bythe disc 32 and the walls of the housing 16. The movement of air, asviewed from FIGURE 2, is in a counterclockwise direction for both setsof vanes 40 and 44, although the movement of air may be clockwisewithout affecting the operation of the combustion head 10. A sufficientnumber of vanes 40 and 44, having the general configuration of convoluteprotuberances, are required in order to provide uniform distribution ofair and proper turbulence, in order to provide the desired results; ithas been found that about 10-14 vanes are satisfactory for both sets.

Since the combustion head housing 16 and cooperating disc 32 are indirect contact with or in close proximity to the flame F, both the disc32 and combustion head 10 are to be made of heat resistant metal.Preferably a high temperature stainless steel is used; AISI type 30astainless steel is particularly satisfactory.

In operation, when oil is sprayed in a fine mist or atomized by thenozzle 22, it is ignited by a spark S passing between the ignitionpoints 22. Simultaneously, air is directed by a blower (not shown)through the air supply tube 14 in a direction from the nozzle outwardlythrough the central aperture 30 at the coned end 26 of the housing 16.The air passing through the inner set and outer set of vanes 40 and 44create air currents or turbulence across the rim 42 adjacent the centralopening 36 of the disc 32. Similarly air or eddy currents are set up atthe outer edges of the vanes 40 and 44; the air currents at the innerset of openings 41 draw some of the fine oil spray from the nozzle 22 tothe zone of low velocity opposite the rim 42. This enables the flame Fto be maintained at the rim 42 and at the edges of the vanes 40, thuspreventing the flame F from drifting away from the burner, as commonlyencountered with conventional burners. Most of the air required forcombustion is then admitted to the flame F through the larger openings44 and through the central opening 36 in the disc 32. 1 The air from theopenings 4'4, flowing tangentially into the chamber formed between thecome 26 and disc 32 creates the air turbulence necessary to produce asubstantially brush shaped flame.

Preferably, the coned portion 26 of the combustion head housing 16extends into the combustion chamber (not shown). Due to the proximity ofthe flame F to the coned portion 26, the cone becomes extremely hot; thecone 26 then causes preheating of the air passing through the second setof openings 44, prior to introduction thereof to the flame F. Thisresults in a flame which is of high efficiency and is clean burning;furthermore, the inwardly directed cone 26 causes the air to be directedtowards the flame F.

While in the foregoing there has been provided a detailed description ofa particular embodiment of the present invention, it is to be understoodthat all equivalents obvious to those having skill in the art are to beincluded within the scope of the invention as claimed.

What we claim and desire to secure by Letters Patent 1. An oil burnercombustion head wherein said combustion head is mounted on an air supplytube and an oil spray nozzle is centrally located within said air tubeand having ignition means adjacent the spray nozzle, said combustionhead comprising a substantially cylindrical housing, an outer endportion on said hoising, a disc mounted interior of said housingintermediate said outer end portion and said nozzle and transverse tothe axis of said housing, said outer end and said disc defining achamber within said housing, said d c h g a centra opening defining aninner rim and an annular portion, a first set of openings in saidannular portion defined by convolute protuberances, said first set ofopenings being spaced inwardly from said central opening for creating(air currents flowing generally tangentially into said chamber fordrawing some of the fine oil spray from said nozzle to a zone of lowvelocity opposite said rim whereby the burner flame is maintained inclose proximity to said rim and to said first set of openings, and asecond set of openings in said annular portion intermediate said firstset of openings and the inner surface of said housing, said second setof openings being defined by convolute protuberances for tangentiallydirecting air into said-chamber for creating aif turbulence to provide asubstantially brush-shaped flame and also assisting said first set ofopenings in creating air currents for maintaining said flame in closeproximity to said disc.

2. Oil burner means comprising an air supply tube, an oil spray nozzlemounted within said air supply tube, a combustion housing secured to theouter end of said air supply tube, an inwardly coned outer end on saidhousing, a disc mounted interior of said housing intermediate said conedend and said nozzle, said disc being transverse to the axis of saidhousing and having a central opening defining an inner rim and anannular portion, said disc and said coned end defining a chambertherebetween and within said housing, a first set of openings in saidannular portion defined by convolute protuberances spaced inwardly ofsaid central portion for creating air currents flowing generallytangentially into said chamber for drawing some of the fine oil sprayfrom said nozzle to a zone of low velocity opposite said rim whereby theburner flame is maintained in close proximity to said rim and said firstset of openings, and a second set of openings in said annular portiondefined by convolute protuberances positioned outwardly of said firstset of openings and tangentially directing air from said air supply tubeinto said chamber for creating air turbulence to provide a substantiallybrush-shape flame and also directing air to said coned end so as to heatair prior to introduction thereof into the burner flame and furtherassisting in maintaining the burner flame in close proximity to saiddisc.

3. The oil burner means of claim 2 wherein said first set of openings issmaller in size than said secondset, and all of said openings direct airin the same swirling direction and substantially tranverse to the axisof said housing.

4. Oil burner means comprising an air supply tube, an oil supply nozzlecentrally mounted within said air supply tube, ignition means adjacentthe nozzle, a substantially cylindrical housing secured to the end ofsaid air supply'tube, an inwardly coned outer end portion on saidhousing, an annular plate mounted along the inner surface of saidhousing and being transverse to the axis of said housing, said platebeing located forward of said spray nozzle, rearward of said coned end,and having a central opening defining an inner rim and an annularportion, said central opening being in substantial alignment with saidnozzle and permitting oil spray from said nozzle to pass therethrough,said plate and said coned end defining a chamber therebetween and withinsaid housing, a first set of vanes defined by convolute protuberancesspaced from each other in said annular portion and being locatedinwardly of said central opening, said first set of vanes directing airsubstantially tangentially into said chamber for drawing some of thefine oil spray from said nozzle to a zone of low velocity opposite saidrim whereby the burner flame is maintained in close proximity to saidrim and to said first set of vanes, and a second set of vanes of largerdimension than said first set of vanes, said second set of vanes definedby convolute protuberances, said second set of 5 6 vanes tangentiallydirecting air into said chamber from References Cited by the Examinersaid air supply tube and creating air turbulence to pro- UNITED STATESPATENTS vide a substantially brush-shaped flame and also directing airto said coned end portion to preheat the air pass- 1,003,873 9/1911 Q158*76 ing through said second set of vanes prior to introduc- 51,102,510 7/1914 Insh 158 1'5 tion thereof to the flame, said second setof vanes 2,347,594 4/1944 De Lm 158 76 2,976,919 3/1961 Sanborn 158-76further assisting in creating air currents for maintaining said burnerflame in close proximity to said plate, both 4 of said sets of vanesdirecting the air in a swirling direc- FREDERICK MATTESON P'lmaryExamlner' tion Within said chamber. 10 E. G. FAVORS, Assistant Examiner.

1. AN OIL BURNER COMBUSTION HEAD WHEREIN SAID COMBUSTION HEAD IS MOUNTEDON SAID AIR SUPPLY TUBE AND AN OIL SPRAY NOZZLE IS CENTRALLY LOCATEDWITHIN SAID AIR TUBE AND HAVING IGNITION MEANS ADJACENT TEH SPRAYNOZZLE, SAID COMBUSTION HEAD COMPRISING A SUBSTANTIALLY CYLINDRICALHOUSING, AN OUTER END PORTION ON SAID HOUSING, A DISC MOUNTED INTERIOROF SAID HOUSING INTERMEDIATE SAID OUTER END PORTION AND SAID NOZZLE ANDTRANSVERSE TO THE AXIS OF SAID HOUSING, SAID OUTER END AND SAID DISCDEFINING A CHAMBER WITHIN SAID HOUSING, SAID DISC HAVING A CENTRALOPENING DEFINING AN INNER RIM AND AN ANNULAR PORTION, A FIRST SET OFOPENINGS IN SAID ANNULAR PORTION DEFINED BY CONVOLUTE PROTUBERANCES,SAID FIRST SET OF OPENINGS BEING SPACED INWARDLY FROM SAID CENTRALOPENING FOR CREATING AIR CURRENTS FLOWING GENERALLY TANGENTIALLY INTOSAID CHAMBER FOR DRAWING SOME OF THE FINE OIL SPRAY FROM SAID NOZZLE TOA ZONE OF LOW VELOCITY OPPOSITE SAID RIM WHEREBY THE BURNER FLAME ISMAINTAINED IN CLOSE PROXIMITY OF SAID RIM AND TO SAID FIRST SET OFOPENINGS, AND A SECOND SET OF OPENINGS IN SAID ANNULAR PORTIONINTERMEDIATE SAID FIRST SET OF OPENINGS AND THE INNER SURFACE OF SAIDHOUSING, SAID SECOND SET OF OPENINGS BEING DEFINED BY CONVOLUTEPROTUBERANCES FOR TANGENTIALLY DIRECTING AIR INTO SAID CHAMBER FORCREATING AIR TURBULENCE TO PROVIDE A SUBSTANTIALLY BRUSH-SHAPED FLAMEAND ALSO ASSISTING SAID FIRST SET OF OPENINGS IN CREATING AIR CURRENTSFOR MAINTAINING SAID FLAME IN CLOSE PROXIMITY TO SAID DISC.